Electric welding-machine for forming electrical contacts.



. W. F. HOSFORD. ELECTRIC WELDING MACHINE FOR ronnmc ELECTRICAL corn/ms.

APPLICATION FILED SEPT-24. I915. 1,292,892. I

Patented Jan. 28, I919.

12 SHEETS-SHEEI I.

W. F. HOSFORD. ELECTRIC WELDING MACHINE FOR FORMING ELECTRICAL CONTACTS.

APPLICATION FILED SEPT-24, I915- Patented Jan. 28, 1919.

l2 SHEETS-SHEET 2.

W. F. HOSFORD. ELECTRIC WELDING MACHINE FOR FORMING ELECTRICAL CONTACTS.

APPLICATION FILED SEPT-24,1915.

12 SHEETSSHEEI 3.

Patented Jan. 28, 1919.

W. F. HOSFORU.

ELECTRIC WELDING MACHINE FOR FORMING ELECTRICAL CONTACTS. APPLICATIONFILED SEPT-24, I9I5- Patented Jan. 28, 1919.

I2 SHEETSSHEET 4.

W. F. HOSFORD. ELECTRIC WELDING MACHINE FOR FORMING ELECTRICAL CONTACTS.

APPLICATION FILED SEPT-24. 1915- 1,292,892.

Patented Jan. 28, I919 12 SHEETS-SHEEI 5.

pZzmZL/Vosfqrd E W W. F. HOSFORD.

ELECTRIC WELDING MACHINE FOR FORMING ELECTRICAL CONTACTS.

12 SHEETS-SHEET I.

Patented Jan. 28, 1919.

W. F. HOSFORD.

APPLICATION FILED SEPT.24.1915.

ELECTRIC WELDING MACHINE FOR FORMING ELECTRICAL CONTACTS.

W. F. HOSFORD.

ELECTRIC WELDING MACHINE FOR FORMING ELECTRICAL CONTACTS.

APPLICATION FILED SEPT-24.1%.). I

Patented Jan. 28, 1919 2 SHEETS-SHEEI B.

w. F. HOSFORDL ELECTRIC WELDING MACHINE FOR FORMING ELECTRBCAL CONTACTS-I APPLICATION FILED SEPT-24, 1915- 1,292,892.

Patentd Jan. 28, 1919.

w. F. HOSFORD. ELECTRIC WELDING MACHINE FOR FORMING ELECTRICAL CONTACTS.

APPLICATION FILED SEPT-24,19I5. 7 1,292,892. Patented Jan.28,1919.

- I2 SHEETSSHEET H.

III

E39 35/ 233 W 7 L 2 /4 242 l E38 I 2 I 240 26 g Me 727 077 6 c'Z&'Qm Iff/osforczi w. F. HOSFORD. ELECTRIC WELDING MACHINE FOR FORMINGELECTRICAL CONTACTS.

APPLTCATION FILED SEPT-24.1915.

Patented Jan. 28, 1919.

l2 SHEETS-SHEET 12.

herir 7G2 UNITED STATES PATENT OFFICE.

WILLIAM .HOSFORD, OF OAK PARK, ILLINOIS, ASSIGNOR, BY MESNE ASSIGNMENTS,T0 WESTERN ELECTRIC COMPANY, INCORPORATED, A CORPORATION OF NEW YORK.

ELECTRIC WELDING-MACHINE FOR FORMING ELECTRICAL CONTACTS.

Specification of Letters Patent.

Patented Jan. 28, 1919.

w Application filed September 24, 1915. Serial No. 52,514.

To all whom it may concern:

Beit known that 1, WILLIAM F. Hosronn, a citizen of the United States,residing at Oak Park, in thecounty of Cook and State of Illinois, haveinvented certain new and useful Improvements in ElectricWelding-Machines for Forming Electrical Contacts, of which the followingis a full, clear, concise, and exact. description.

This invention relates to a machine for electrically welding contacts orthe like, as, for example, welding platinum contact heads to a shank orother support, forming rivets or studs, to be used particularly withswitch contact springs and analogous electrical devices.

The invention contemplates a sequence of operations in which the ends oftwo wires, one of platinum or other material suitable for electricalcontacts, and the other of less expensive conducting material, arepressed against each other and the abutting ends welded together by thepassage of an electric current through the adjacent ends of said wires.Both wires are then cut, the platinum wire being out very short and theother wire, which maybe of German silver, for example, being cutsomewhat longerv to form a shank with a platinum tip, which tip, as afurther and final step in the sequence of operations, may be shaped togive it a conical point, a flat disk shape, or any other desired form.

In its preferred form, the machine which is employed in carrying outthis invention comprises a pair of chucks, through'which the two wiresare fed,'said chucks gripping the respective wires and bringing them.together. In this position the circuit is closed momentarily and thewires welded end to end. Both wires arethen cut, the severed lengthbeing transferred by a reciprocating carriage to an anvil having a holewhich receives the German silver shank, while the platinum head is beingformed by a plurality of tools which are pressed down upon it insuccession. The stud or rivet thus formed is then ejected from the holeand brushed off the support into a receptacle.

The several features of this invention may be more readily understood byreference to the accompanying drawings, in which Figure 1 is a frontelevation, partly in section, of a machine embodying the invention;

Fig. 2 is a plan View thereof, with certain parts removed for the sakeof clearness;

F g. 3 is an end elevation of the machine;

Fig. 4 is a section on the line 1--4 of Fig. 1;

Fig. 5 is a section on the line 5-5 of Fig 1;

ig. 6 is a half elevation and half section on the line 66 of Fig. 2;

Fig. 7 is a section on the line 7-7 of Fig. 4;

Fig. 8 is a section on the line 88 of Fig. 4;

Fig. 9 is a section taken on the line 9-9 of Fig. 4;

Fig. 10 is a plan view of the carriage in its initial position;

Fig. 11 is a front elevation of the welding and heading mechanism, thelatter being shown partially in section;

Fig. 12 is an enlarged sectional elevation of the heading mechanism in aplane at right angles to the section in Fig. 11;

Fig. 13 is a plan of the switch mechanism with the actuating parts insection;

Fig. 1a is a similar plan view with the actuating parts in a differentrelative position;

Fig. 15 is a side elevation of the switch mechanism;

16 is a diagram of the circuit connections;

Figs. 17, 18 and 19 are elevations on a large scale of various types .ofcomposite contacts which may be made by the machine.

The various parts of the machine are supported in a suitable frame orstandard, the base of which is indicated by reference 1. The main shaft2, from which the various parts are driven, is arranged horizontallynear the top of the machine. It may be driven from any suitable sourceof power. For this purpose, an electric motor 3 is provided, which ismounted on the frame of the machine and which drives said main shaftthrough suitable reduction gearing 4, 5, 6, 7 8 and 9. A clutch,hereinafter described, may also be provided, whereby the machine stopsafter each complete cycle until'started by the operator. The main shaft2 drives a pair of vertical shafts 10, 11. These shafts have variouscams mounted thereon, which control the cycle of operations of themachine. The shaft 10 is driven from the shaft 2 through beveled gears12, 13. The shaft 11 is driven from the shaft 10 by gears 14, 15,mounted on the respective shafts. The main shaft 2 is provided with ahand wheel 16, whereby-the machine may be operated slowly by hand wheninspect ing it or adjusting it.

As seen in Figs. 4 and 5, the vertical shaft 10 is provided with asleeve 17 having a spline connection, whereby it rotates therewith butmay slide thereon to adjust it vertically. Said sleeve carries a cam 18at its upper end in the form of a radial flange with an offset portion19. It also carries further cams 20, 21, 22, 23 located between collars24, 25. It is provided at an intermediate portion with a pair of collars26, which receive between them a steel supporting plate 27 secured byscrews 28 to a vertically adjustable frame, hereinafter described. Theposition of the sleeve vertically is determined by this supportingplate. At the lower end of the shaft, a two-faced cam 30 is located. Theupper cam 18 and the lower cam 30 rock upper and lower armsrespectively, by means of which two chucks are made to approach andrecede from each other, to feed the platinum and German silver wirestoward each other.

The upper arm 31 is pivoted about the pin 32 and is provided with a pairof rollers 33 which engage opposite sides of the flange 18. Said arm hasan opening near its free end within which a screw-threaded sleeve 35 isreceived, said sleeve surrounding a stud 36 which slides freelytherethrough, said stud being screwed into a second sleeve 37 at itslower end. Said sleeve is. normally impelled downwardly by means of aspring 38 which bears at its upper end against the upper sleeve 35 andat its lower end against a nut 39. A flexible conductor 40 is clamped atan intermediate portion between the lower end of the sleeve 35 and awasher 41. Good electrical contact is thus made with the foregoingparts, the other end of the fleizible conductor being connected to aterminal member 42 to which a bus bar 43 is clamped. A second bus bar 44is also provided which makes contact with a second terminal member 45and is clamped thereto between a washer 46 and a nut 47, the secondterminal member being in the form of a sleeve concentric with andseparated from the first terminal member. It is insulated therefrom andfrom the frame of the machine by suitable insulation 48, 49.

The chuck as a whole is slidably mounted in an opening in a verticallyadjustable frame 50, said opening having a liner 51 of insulation whichincloses a cylinder 52. The lower end of the sleeve 37 is secured in acylindrical block 54 constituting the body'of the chuck and arranged toslide up and down within said cylinder. A plurality of jaws 55 fitwithin a conical recess within said block 54 and are normally impelledupwardly by a spring 56, whereby they grip a 1 plurality of inner copperaws 57, causing the latter to grip the platinum wire ,58 and make goodcontact therewith. Said inner jaws are locked in place within said outerjaws by means of a circumferential shoulder 59, but are removable to.permit replacement if burnt out. The jaws and the spring are preventedfrom dropping from the block 54 by means of a ring-60 screwed into theopen end thereof. Assuming that the lower end of the platinum wire 58 isheld against upward movement, it will be seen that when the chuck islifted by the pivoted arm 31, the jaws thereof slide upwardly along thewire 58, the friction between the wire and said jaws serving to unseatthe latter from their conical seat against the action of the spring 56.,When the chuck is moved downwardly, however, the jaws grip the wire andadvance it. The spring 38 constitutes yielding means, whereby thedownward movement of the chuck may be stopped somewhat prior to thedownward limit of movement of the pivoted arm 31 without injuring theapparatus, and insures pressure on the abutting ends of the wires. I

The entire frame 50, supporting the upper chuck, is adjustablevertically to vary the amountof platinum in the head and also the lengthof the German silver shank. As shown in Figs. 2 and 4, the frame 50 hasa narrow portion 61 which slides between parallel flanges 62constituting part of the main frame. The frame 50 is adjusted verticallyby means of a stud 63 at the upper end thereof. Said frame is clamped inadjusted position by means of a bolt 64. It will be seen that 'when theframe 50 is adjusted vertically, the upper chuck and associated partsare .carried with it. as well as the jaws, the nippers, their associatedparts and the sleeve 17 carrying the various cams. Themovement of saidsleeve is effected by virtue of the plate 27 received between thecollars 26. as previously explained.

The German silver wire 65 is fed upwardly in a manner quite similar tothat above described. The details of the chuck,

however, are somewhat different, the inner copper jaws being omitted.The cam 30 at the lower end of the shaft 10 rocks the arm- 66 up anddown. Said armis pivoted about the pm 67 and carries a roller 68, whichrides in the groove of the cam 30. At its outer end which are engaged bythe pin 69 On the arm therewith and slide in suitable slots.

aaeaeea 66. The rod is thus raised and lowered toward the end of themovement of the pin 69. A coarse adjustment of its movement is obtainedthrough the collars 71, 72, and a fine adjustment through the studs 74.The rod 70 carries an arm 75, which raises and lowers the chuck member76, being secured to the lower end thereof by means of a nut 77. Saidchuck member slides within a block 7 8 and has a conical seat in anopening atits upper end within which a plurality of jaws 79 are normallyseated by means of a spring 80. The spring bears also against a disk 81which closes said opening. Assuming the German silver wire to be heldagainst downward movement, it will be seen that when the chuck movesdownwardly the jaws slip along the wire, but when it moves upwardly theyadvance the wire. Said wire passes through an accurately formed openingin a hard steel plate or die 82, forced into a support 83, dovetailedintothe upper end of the block 7 8. The platinum wire is carried on asuitable reel or spool 85, mounted to turn freely on a stud 86,supported by an arm 87. The German silver wire is mounted on a spool 88,supported on a stud 89 in the lower part of the machine. The operationof the machine is such that the ends of the wire are first weldedtogether and the parts thus welded are out off from the respectivewires, forming a composite member, the lower part of which consists of ashort length of German silver wire with a tip or head of platinumintegrally united thereto. The diameter of the two wires may be the sameor either may be larger than the other. In forming a rivet, such asshown in Fig. 17 the platinum wire may be of somewhat greater diameterthan the German silver wire, although, since the platinum tip is upsetand formed into a head, this need not necessarilybe the case. Forcertain purposes, the wires may be of the same diameter as shown in Fig.19, and no head formed at all.

The means for holding theGerman silver wire during the brief intervalthat the platinum wire is being welded to it, constituting also themeans for establishing the welding circuit, will now be described (Fig.8). A pair of levers 90, 91 are pivotally mounted on a stud 92. In orderto insure a hard, smooth surface at the rear ends against which the cams22, 23 may slide, L-shaped members 93, 94: are provided, which divergeslightly. These members slide longitudinally in suitable ways, and eachmay be adj usted by a screw 95 whereby the proper distance between themmay be arrived at. Said members are locked in'their position ofadjustment by means of screws 96, which traTxiel 1e copper clamps100,101 are carried at the free ends of said levers in suitable carriers102 to which the flexible conductor 103 is connected, whereby thecircuit may be completed through said jaws. The carriers 102 areadjustably secured within openings at the outer ends of the levers 90,91, the adjustment being effected in each case by means of an eccentricstud 104:, the inner end of which turns in a bushing 105 and the outerend of which turns in a suitable sleeve 106, which is screwed into anopening in the lever. The clamps are brought together once during eachrevolution of the shaft 10 by means of the cams 22, 23. These cams areidentical in outline and are superimposed but are arranged 180 degreesapart. Each cam cooperates with one of the members 93, 94 but not withthe other, one of said members being arranged somewhat higher than theother to permit this operation. The clamps are normally held apart by aspring 107 which draws the levers 90, 91 together, and they may beremoved from thelr carriers to replace them.

During the welding operation, the upper chuck grips the wire tighterthan the lower chuck in order to insure good electrical con tacttherewith. The lower chuck is not re lied on for making electricalcontact, as the copper clamps 100, 101 perform this function, thecircuit being completed through the conductors 103, 108 and 109 to theterminal member 45 and bus bar is.

After the welding operation has taken place,the platinum wire is cut ofjust above the weld by means of suitable nippers actuated by mechanismwhich will now 'be described (Fig. 7). Directly above the pair ofpivoted levers which operate the clamping members, is a second pair oflevers 110, 111 mounted on the same stud 92. The rear ends of saidlevers are provided with adjustable members similar to those previouslydescribed, and they are moved apart by the rotation of the cams 20, 21,which are mounted 180 degrees apart, similarly to the cams 22, 23. Theforward ends carry the knife blades 112, 113, which meet momentarily,thus cutting the wire after the welding has been completed. The bladesare normally held apart by means of a spring 11 1.

The operation .of the machine is such that just prior to the cutting offof the platinum wire, the upper chuck is raised, enabling the jawsthereof to take a new grip on the wire, whereby, when said chuck issubsequently lowered, a new length of wire is presented for the weldingoperation. During this upward movement of the chuck, the clamps 100,101- retain their hold on the German silver wire in order to resist theupward pull, and hold the platinum wire down while the jaws slipupwardly along it. After the chuck has moved upwardly, the nippers outofi the platinum wire in the manner previously described. While'the jawsstill grip the wire, the lower chuck. begins to descend,

sliding along said wire preparatory to taking a new grip thereon. Beforesaid chuck has completed its descent, however, said jaws release theirgrip on the end of the German silver wire which carries the platinumtip, said Wire being drawn down a small amount, just enough so that saidtip clears the underside of said clamps with enough of the German silverprojecting through the opening in the die to provide a shank of thedesired length.

As the next step of the operation, the German silver wire is shearedoff, and the small partially completed rivet thus formed 1s moved by atraveling carriage beneath a pair of hammers which shape up the head tothe desired form. The carriage, includes the shearing mechanism, willnow be described. It consists of a bar of metal 119 having asuperimposed block 120 and sliding in suitable ways 121, extendingtransversely across the front of the machine. A cover plate 122 issecured thereto and extends the entire width of the machine as shown inFigs. 1 and 2, thereby covering the opening between said ways.The-carriage is moved back and forth by means of a stud 123 screwed intothe bar 119 as shown in Fig. 12, said stud being surrounded by a sleeveor roller 124 nd reciprocated by an arm 125, having at its outer end aslot within which the roller is received, and being mounted at its otherend on the pivotally The arm 125 is caused to rock stud 126.

about its pivot by a positive driving mecha-= nism dur ng part of itsmovement only, most of its motion being derived from a second arm 127also pivotally mounted on the same stud 126. and having frictionalengagement with said first arm, whereby one may drive the otherfrictionally but permit a certain if necessary. The connection for thisslip purpose consists of a slot 128 in'the outer' end of the pivoted arm127 through which a stud 129v passes. A spring 130 which surrounds saidstud causes the arm 127 to press upwardly against the arm 125. Both armsare provided with openings 131, 132 through which the vertical shaft 11passes, the wall of the openings constituting cam surfaces. An arm 133is mounted to turn with the shaft 11 and carries a roller 134 at itsouter end, which roller rides along the wall of the opening 132, therebyimparting the desired back and forth movement to the arm 127 and thenceto the arm 125 and to the carriage. The arm 133 engages the wall of theopening 131 at one oint in its rotation, thereby positively driving thearm 125, at the time when the carriage begins its travel, to provide forthe. shearm silver Wire. As will herea r be apparent, it is desirable toconfine the travel of the carriage to very accurate limits, and for thiswhich of the German reason the travel is not determined simply by theback and forth movement of the arm 127, but the lost motion mechanismjust described is provided in conjunction'with a pair of positive stopswhich may be accurately adjusted. Said stops 135, 136 (Fig. 9) haveinclined faces and are adjustable from front to rear by means of screws137. Said stops are engaged by the corresponding inclined faces 138, 139of blocks secured to the sliding cover plate 122 by means of screws 140.One of said blocks constitutes the main body of the carriage 119, theother block 141 being in alinement therewith. The travel of the carriageunder the influence of the arm 127 would ordinarily be slightly greaterthan the limits determined by said stops, as a result of which the arm127 slides over the arm 125 a small amount during the back and forthreciprocation. To take up Wear, one side of the ways is formed by anadjustable bar 142 which may be moved rearwardly by screws 143.

The object of accurately limiting the travel of the carriage is topermit the rivet to be carried from the point where it is welded to asmall hole 145, in what may be termed an anvil 146, into which hole itis thereafter pushed and held while the head is being shaped up. It istherefore essential to stop it exactly over said hole. During thetraveling movement, the rivet is yieldingly held between two members147, 148. The member 147 is a tool steel arm secured to the top of theblock. Its lower edge constitutes a shearing knife and its vertical faceis provided with a vertical recess 149, within which recess the rivet isyieldingly held by the arm 148 which is pivoted to the block 120 aboutthe stud 150. At the time the rivet is welded, the members 147, 148 areon opposite sides of said rivet, and are spread apart slightly so as notto interfere with said operation. (See Fig. 10.) They are held apart bya downward projection 155 on the arm 148 which engages a stationary projection 156 during the travel of the carnage to the right, whereupon saidmembers are held apart against the action of the spring 157. (See alsoFig. 11.) As soon as the carriage starts to the left, being positivelydriven at this point, the arm 147 shears olf the German silver wire, andsimultaneously the shank of the rivet is seized between the members 147,148 which come together, hold it in the recess 149 and carry it to apoint exactly above the hole 145 in the anvil into which hole it isimmediately pushed, as hereinafter described. (See Figs. .11 and 12.)

The mechanism for shaping the rivet head will nowbe described. Within avertical opening in a part 160 of the main frame of the machine, aplunger 161 is mounted which is normally held in uppermost position bymeans of a spring 162 which bears against a shoulder 163 thereon. Saidplunger is moved downward intermittently, however, by means of a pivotedarm 16% by which it is carried. Said arm is mounted to turn about thestud 165, and at one end supports the plunger by means of a stud 166,the other end being engaged by a pair of rollers 167 mounted on oppositesides of a suitable arm 168 fast to the main shaft 2. In order toaccurately adjust the movement of'the arm 164 and to provide for more ofa throw when one roller strikes it than when the other roller strikesit, a pair of adjustable devices 169, 170 are provided, similar to thosepreviously described, each of which is engaged by one roller only.

As the plunger 161 moves downwardly, it depresses either of tWo toolholders arranged directly beneath it and mounted in a carriage, wherebyone or the other of said-tool holders maybe brought into positionbeneath said plunger in alinement therewith. The carriage, as seen inFigs. 11 and 12, consists of a block of metal 175 which slides in waysmade up of adjustable wedges 176, 17 7 See also Fig. 7. These wedges areadjustable by means of screws 178, whereby they may be movedlongitudinally with their inner surfaces always parallel. Thisadjustment permits the carriage as a whole to be adjusted to the frontor rear a very small amount. In addition to the block 17 5, the carriageconsists of a lower block 180 secured thereto by studs 181. The carriageas a whole (see Fig. 8) is made to reciprocate by means of a segmentalrack 182, the teeth of which engage teeth 183 formed in said lower block180. The arm 182 is pivoted about a stud 184. It is reciprocated by acam consisting of a disk 185 which turns with the shaft 11 and has a camgroove 186 therein, which receives a roller 187 carried by said arm 182.As the shaft turns, the carriage is reciprocated, any overthrow beingprevented by positive stops in the form of nuts 188, 189 on ascrew-threaded rod 190 projecting from the lower block 180, which nutsengage the sides of a bracket 191 secured by a screw 192 to themainframe.

The lower block 180 has two openings therethrough within which the toolholders 195, 196 are mounted, the latter being normally held inuppermost position by means of suitable springs 197, longitudinalmovementthereof being limited by pins 198 which project through slots199. The lower end of each holder is recessed to receive a tool, bymeans of which the head of the rivet may be given the desiredconfiguration. In the present case, the first tool 200 is arranged topress down the platinum head and widen it or upset it. The carriage isthen moved to bring the second holder 195 in alinement 161, whereuponsecond tool 201 is pressed down against the previously formed head andgives it a rounded top resembling a rivet head. The extent of thedownward movement of the tools may be independently adjusted. As thefirst tool pushes the rivet into the hole in the anvil, the yielding arm148 separates from the fixed arm 1 17 to whatever extent is necessary,and the carriage on which the arms are mounted immediately begins areturn movement. The rear end of the yielding arm 148 is caughtmomentarily by the rivet as it projects from the hole, said endeventually freeing itself as it is swung to diagonal position. After therivet is headed, it is ejected from the hole and swept 0d the anvil by aresilient arm 202 mounted on the arm 1 18. Mechanism for ejecting therivet from the hole in the anvil will now be described.

As previously stated, the anvil consists of a small plate 146 of hardmetal. It is received within a cap 203, the latter being secured byscrews 204 to a suitable base 205. A vertical reciprocal plunger 206 ismounted within said base 205 and is provided with an ejector pin 207which fits within the opening 145. It is normally held in lowermostposition by a spring 208 but is adapted to be elevated by means of atransverse latch 209. Said latch has a pair of ratchet teeth 210 on theupper face thereof which engage corresponding teeth 211 on the undersurface of the plunger, whereby when said latch is moved to the rear(see Fig. 12) .the plunger will be elevated. The latch 209 is normallyimpelled forwardly by means of a spring 212. The outer end of said latchis beveled at 213, whereupon it may engage a correspondingly beveledsurface on a stop arm 214. Said stop arm is mounted on the travelingcarriage 120, being pivoted on a pin 215 and yieldingly held against astop 216 by means of a spring 217. As the carriage 120 moves to theleft, the-stop arm 214 engages the beveled end of the latch and moves itrearwardly, thereby raising the ejector pin and ejecting the rivet fromthe hole in the anvil. The stop arm 214 travels beyond the projectingendof the latch, and on its return movement rides over it by virtue ofthe yielding mounting described.

The heating circuit is controlled in part by a suitable switch mechanismmounted in a receptacle 220 at one end of the machine. The main shaft 2passes through said receptacle and has mounted thereon a sleeve 221compelled by a yieldingly held pin 222 to turn with said shaft when itrotates in one direction, but not in the other if obstructed.

The sleeve has an arc-shaped earn 223 pro- 1 jecting therefrom. Asimilarly mounted cam 22% is spaced from the first cam on said sleeve.As the shaft turns in the direction indicated by the arrow, the cam 223engages a projection 225, which latter, by means of insulation 226, ismounted on a resilient strip 227. Said strip carries a contact 228 atits free end. The other end is secured to a member 229, which latter ismounted on an insulating frame 230 having a'lateral arm 231 projectingtherefrom. When the projection 225 is engaged by the beveled front endof the cam 223, the contact 228 is pressed against a stationary contact232, thereby closing the circuit at this point. In a similar manner, thecam .224 engages a projection 233 mounted on, but insulated from, themetal strip 234, the latter being secured to a conducting member 235 atone end and carrying a contact 236 at its other end.

- Said contact 236 is normally in contact with the stationary contact232 but is moved out of contact therewith whenever the front endthreadedat these points whereby rotation thereof will cause said arms toapproach or recede from each other. The spindle is Y mounted in anopening in the support 240 and secured against longitudinal movement bycollars 241. It is rotated by a knurled head 242. The insulating frames230, 237 I are guided in their back and forth movement by suitableguides 243 and .secured against movement by a screw 244. The effect ofthis adjustment is to displace the projections 225, 233 longitudinallywith respect to each other, whereby they are engaged by the rotatingcontacts at different relative parts of the rotation thereof. Thesequence of operations is such that the contact 236 is first moved awayfrom the stationary contact 232 and immediately thereafter the contact228 is moved against said stationary contact. However, the circuit isnot closed until contact 236 is allowed to snap back against thestationary contact, almost immediately after which the contact 228 ispermitted to spring away from said stationary contact. The circuit isthus closed for a very short interval of time, due to the fact to themotor 1 in the remaining sheets of the drawings. A pair of conductors252 lead tend to terminals 254, one of which is connected directly tothe primary windings 255 of the transformer. The other conductor hasconnected in series therewith a switch 256 for controlling the circuitof said primary, said switch being the one, the mechanical features ofwhich are illustrated in Figs. 13, 14, 15. The circuit leads from saidswitch to a suitable selector switch 257 consisting of a pivoted arm 258and a series of contacts 259, connected by conductors 260 to the turnsof the primary in such manner as to vary the number of turns in series,thereby regulating the amount of energy consumed during the weldingoperation. The secondary 261 is illustrated diagrammatically as beingconnected to the welding terminals 262, 263.

The selector switch 257 is mounted preferably in the base of themachine, as shown in Fig. 9. It is controlled by the operator by meansof a knurled knob 264. The transformer 265 is also mounted in the baseof the machine. The conductors 266, 267 lead therefrom to the bus bars43, 44 previously mentioned. The motor switch is controlled by theoperator through a suitable switch 268 at the front of the machine, andthe transformer switch is controlled from a similar switch 269. Variousconduits 270, 271, 272 and 273 are provided within which are located thevarious conductors necessary to connect up the different parts ofthecircuit. The transformer, the various switches and conductors are ofstandard construc tion and need not be described herein.

The machine runs continuously when in operation, although for the pn oseof runmng it intermittently when making the trial runs or adjustment, asuitable clutch may be provided controlled, for example, by a pivotedlever 27 5. (See Figs. 1 and 2.) The beveled free end 276 of said leveris engaged by a curved spring 277 when the main shaft completes onerotation, thereby withdrawing a pin 278 and unlocking the collar 279 onthe main shaft from the continuously rotating gear 9, whereby themachine is stopped until the operator moves the lever 275 out ofengagement with said.

spring.

The operation of the machine may be briefly summarized as follows: Theplatinum and German silver wires are brought together by the two chucksand the weldin current is applied momentarily by the switc operated bythe main shaft. During the welding operation, the German silver wire isheld adjacent to the weld by the copper clamps. The latinum wire isthereafter cut off by the mppers and the German silver wire, released bythe copper clamps, is

naeasea drawn downwardly below said clamps and then sheared oh and movedby the carriage to the anvil where it is headed by two successiveoperations. lt is then ejected from the anvil and swept aside into asuitable receptacle. While the heading operation is taking place, awelding operation is taking place simultaneously, forming a compositebar which is thereafter headed. The machine, therefore, operates atmaximum capacity, since neither the heading mechanism no'r'the weldingmechanism is idle during the operation of the other. As previouslystated, it is not desirable in all cases to form a head out of theplatinum tip, in which case the heading operation is omitted entirely.

W hat is claimed is:

1. in a welding machine, the combination with means for pressing theends of two wires together, of means for passin a welding currentthrough the point or contact thereof, and means for forming the materialadjacent to one side of the weld into a contact.

2.. In a welding machine, the combination with a pair of chucks, ofmeans for moving said chucks toward and away from each other, saidchucks each having jaws adapted to grip a wire, said jaws being arrangedto slip over the wire in each case when the chucks recede from eachother, the jaws of one chuck constituting electrical. contact members,

3. In a welding machine, a pair of chucks for holding and feedingforward the ends of two wires, clamps for holding one or said wiresbetween the end thereof and its chuck, and means for passing a weldingcurrent through said wires between said other chuck and said clamp.

d. In an electrical welding machine, the combination with means forholding two wires in end contact, of means for passing a welding currenttherethrough, and means for shearing olf saidwires on opposite sides ofthe weld.

5. In an electrical welding machine, the combination with a pair ofchucks for bold ing two wires in end contact, of means for gripping oneof said wires adjacent to the end thereof, means for shearing the otheror" said wires adjacent to the end thereof, and means for shearing thefirst wire between its chuck and its end.

6. In an electrical welding machine, the combination with a pair ofchucks for holdin two wires in end contact of clam s for gripping one ofsaid wires adjacent to the end thereof, means for passing a weldingcurrent through one of said chucks and said clamp and the interveningportions of the two wires, means for shearing one of said wires adjacentto said weld, and means for shearing the other or said wires at adistance therefrom.

7. In an electrical welding machine, means for holding two wires in endcontact, means for directing a welding current therethrough, means forshearing the wires on opposite sides of the welded joint, and means forremoving the article thus sheared.

8. In a machine of the class described, means for welding the abuttingend of wires together to form composite bars and means for heading thebars to form composite rivets or studs by an operation which issimultaneous with the welding of subsequently formed bars.

9. In a device of the class described, means for welding two dissimilarmetals together, means for shearing the welded portions from theremainder of the stock, a carriage for moving the composite article thusformed to an anvil, and means for shaping said article at said anvil.

10. In a device of the class described, means for welding the abuttingends 01'" wires together to form composite bars, and means for headingthe bars to form'composits rivets or studs by an operation which issimultaneous with the welding of subsequently formed bars.

11. In a welding machine, a main shaft, two auxiliary shafts driventhereby, a pair of chucks, connections between said chucks and one orsaid shafts whereby the former are made to approach and recede from eachother, and a tool carriage reciprocated by the other of said'shaits.

12. In a welding machine, storage reels for two wires, means for holdingthe ends of said wires in yielding engagement, a main operating shalt,connections between the latter and said means, and a switch operated bysaid main shaft for passing a welding current through said contactingends.

13. In a device of the class described, a main shaft, two auxiliaryshafts driven thereby, means operated by one auxiliary shaft forbringing two wires together to lild weld them, and means operated by theother shaft for shaping the product.

14. In a welding machine, a carriage, a pivoted arm for moving saidcarriage, a shearing blade on said carriage, a second pivoted arm, africtional, connection between said arms whereby the latter may drivethe former, and means for positively driving saild first arm during theshearing operation on y. I

15. In a device of the class described, a carriage, a pair of pivotedarms, a frictional connection between said arms, means for driving oneof said arms positively, positive connections between said other arm andsaid carriage whereby said carriage is driven by said positively drivenarm, and adjustable stops for confining the movement of said carriage toa travel less than it tends to attain.

16. In a welding machine, a carriage hav- 5 ing a pair of yielding arms,one of said arms having a recess to receive a composite bar, the otherof said armsserving to hold said bar in said recess.

17. In a welding machineya carriage, and a pair of cooperating armsthereon, one of 10 said arms constituting a shear blade.

In witness whereof I hereunto subscribe my name this 14th day ofSeptember A. D., 1915.

WILLIAM F. HOSFORD.

